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161.
Abdelhamid  Hani Nasser  Lin  Yu Chih  Wu  Hui-Fen 《Mikrochimica acta》2017,184(5):1517-1527
Microchimica Acta - Laser desorption-ionization mass spectrometry (LDI-MS) is used to determine Hg(II) ions by using thymine-modified chitosan-coated magnetic nanoparticles (TCTS). TCTS...  相似文献   
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Adaptive properties and complex shapes of modern day soft matter components create a challenge for materials applications where mechanical properties of intricate fabricated components cannot be determined from conventional invasive and destructive mechanical tests. In particular, challenges arising from variable mechanical properties of polydimethylsiloxanes (PDMSs) constantly attract wide‐scale attention in the fields of material sciences, biological systems, and microfluidics. Herein, a noninvasive and nondestructive strain‐induced infrared spectroscopic method (S‐FTIR) is developed. S‐FTIR is a method that maps thermo‐mechanical response of PDMS to its strain‐induced spectral fingerprint. From the results of this study, strong correlations of up to 95% between spectral fingerprint of PDMS and its corresponding nonlinear thermo‐mechanical response is seen. Given the nature of these results, it is expected that S‐FTIR will provide an interesting new analytical approach to understand soft materials and allow for the characterization of micro and nanoscale devices composed of these polymeric materials as well. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 359–367  相似文献   
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Research on Chemical Intermediates - Titanium oxide nano-layers were fabricated by a direct electrodeposition method, including Ti as anode and stainless steel as cathode in a non-aqueous media....  相似文献   
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Although a broad variety of classes of bioactive compounds have already been isolated from seaweeds of the genus Dictyota, most different species are still chemically and biologically unexplored. Dictyota species are well-known brown seaweeds belonging to the Dictyotaceae (Phaeophyta). The phytochemical composition within the genus Dictyota has recently received considerable interest, and a vast array of components, including diterpenes, sesquiterepenes, sterols, amino acids, as well as saturated and polyunsaturated fatty acids, have been characterized. The contribution of these valued metabolites to the biological potential, which includes anti-proliferative, anti-microbial, antiviral, antioxidant, anti-inflammatory, and anti-hyperpigmentation activities, of the genus Dictyota has also been explored. Therefore, this is the most comprehensive review, focusing on the published literature relevant to the chemically and pharmacologically diverse biopharmaceuticals isolated from different species of the genus Dictyota during the period from 1976 to now.  相似文献   
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Nonlinear Dynamics - The efficiency of the hardware implementations of fractional-order systems heavily relies on the efficiency of realizing the fractional-order derivative operator. In this work,...  相似文献   
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We consider the problem of large‐data scattering for the quintic nonlinear Schrödinger equation on R × T 2. This equation is critical both at the level of energy and mass. Most notably, we exhibit a new type of profile (a “large‐scale profile”) that controls the asymptotic behavior of the solutions. © 2014 Wiley Periodicals, Inc.  相似文献   
169.
Iron oxides are considered as the promising pseudocapacitive materials for high-performance supercapacitors due to their high theoretical specific capacitance, low cost, environmental benignity, and natural abundance. In this work, we study capacitive behavior of different magnetite (Fe3O4) nanoparticles/carbon black (CB) composites ratios. These composites are synthesized by the coprecipitation method in the presence of ultrasonic waves. The structural and morphological characteristics of the magnetite/CB composites are investigated by X-ray diffraction and scanning electron microscopy, respectively. The electrochemical performance of magnetite/CB composite electrodes is tested by cyclic voltammetry and galvanostatic charge/discharge in a Na2SO4 electrolyte. The results indicate that the magnetite/CB electrodes show typical pseudo-capacitive behavior in Na2SO4 solution. Moreover, in comparison to the pure Fe3O4 (37 F g?1) and carbon black (23 F g?1), the as-prepared 45 % magnetite/CB nanocomposite electrode shows a higher specific capacitance (300 F g?1). Additionally, the supercapacitor device of the magnetite/CB nanocomposite exhibits excellent long cycle life along with 98.5 % specific capacitance retained after 10,000 cycle tests.  相似文献   
170.
A new series of monoselenoquinone and diselenoquinone π complexes, [(η6p‐cymene)Ru(η4‐C6R4SeE)] (R=H, E=Se ( 6 ); R=CH3, E=Se ( 7 ); R=H, E=O ( 8 )), as well as selenolate π complexes [(η6p‐cymene)Ru(η5‐C6H3R2Se)][SbF6] (R=H ( 9 ); R=CH3 ( 10 )), stabilized by arene ruthenium moieties were prepared in good yields through nucleophilic substitution reactions from dichlorinated‐arene and hydroxymonochlorinated‐arene ruthenium complexes [(η6p‐cymene)Ru(C6R4XCl)][SbF6]2 (R=H, X=Cl ( 1 ); R=CH3, X=Cl ( 2 ); R=H, X=OH ( 3 )) as well as the monochlorinated π complexes [(η6p‐cymene)Ru(η5‐C6H3R2Cl)][SbF6]2 (R=H ( 4 ); R=CH3 ( 5 )). The X‐ray crystallographic structures of two of the compounds, [(η6p‐cymene)Ru(η4‐C6Me4Se2)] ( 7 ) and [(η6p‐cymene)Ru(η4‐C6H4SeO)] ( 8 ), were determined. The structures confirm the identity of the target compounds and ascertain the coordination mode of these unprecedented ruthenium π complexes of selenoquinones. Furthermore, these new compounds display relevant cytotoxic properties towards human ovarian cancer cells.  相似文献   
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